"The major cause of bird species loss—indeed, all species loss—is habitat destruction. Habitat modification, fragmentation, and loss is caused by a myriad of human activities, including logging, crop farming, livestock grazing, mining, industrial and residential development, urban sprawl, road building, dam building, and pesticide use.
In a 2000 report by the World Conservation Union surveying 1,173 threatened bird species, habitat loss was the most important threat, affecting 83% of the bird species sampled. Across the United States, little land is left untouched by human development, modification, fragmentation, and pollution. Already human activities have led to the extinction of 10% of the world’s bird species—in some locales, that number rises to as much as 90%. Today more than a thousand bird species are listed as threatened, and scientists predict between 500 and 600 of those will go extinct in the next 50 years.
In the United States, much of the impact on birds is a result of America’s growing population and its even faster-growing development of land. Between 1990 and 2000, the U.S. population grew by 33 million people, the greatest numerical increase the country has ever seen. Future growth is predicted to add 27 million people each decade for the next 30 years.
More significant is that America’s demand for resources is growing disproportionately to its population. A Brookings Institution analysis reveals that urbanized land increased by 47% in the 15 years between 1982 and 1997, even though population only increased by 17%; population in suburbs, meanwhile, increased twice as fast as population in cities. Researchers at Brookings predict that by the year 2030, half of the buildings in which Americans live, work, and shop will have been built after the year 2000. With this level of development and population growth, the serious loss of bird species—due to habitat destruction, pollution, and fragmentation—will continue for decades to come."
Habitat Destruction Bibliography
BirdLife International (2004). Threatened birds of the world 2004. CD-ROM. Cambridge, UK: BirdLife International.
Brooks, Thomas M., Stuart L. Pimm, and Nigel J. Collar. "Deforestation Predicts the Number of Threatened Birds in Insular Southeast Asia." Conservation Biology 11 (1997): 382-394.
Dirzo, Rodolfo, and Peter H. Raven. "Global State of Biodiversity and Loss." Annual Review of Environment and Resources 28 (2003): 137-167.
Jetz, Walter, David S. Wilcove, and Andrew P. Dobson. "Projected Impacts of Climate and Land-Use Change on the Global Diversity of Birds." Public Library of Science Biology 5 (2007): e157,
http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371%2Fjournal.pbio.0050157’.
King, David I., and John H. Rappole. “Population Trends for Migrant Birds in North America: A Summary and Critique.” Defenders of Wildlife (2003).
Myers, Norman, Russell A. Mittermeier, Cristina G. Mittermeier, A. B. Da Fonseca, and Jennifer Kent. "Biodiversity Hotspots For Conservation Priorities." Nature 403 (2000): 853-858.
Pimm, Stuart, Peter Raven, Alan Peterson, Çagan H. Sekercioglu, and Paul R. Ehrlich. "From the Cover: Human Impacts on the Rates of Recent, Present, and Future Bird Extinctions." Proceedings of the National Academy of Science 103 (2006): 10941-10946.
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